Posts Tagged science
Chinese grow cotton on the far side of the moon
Early this year the Chang’e 4 (named for the Chinese Moon goddess) landed on the moon and sent out the Yutu 2 (Chinese for “jade rabbit”) for a short hop on the surface. The mission achieved a first by growing cotton. Never before has mankind grown plants on the surface of another world. Unfortunately, when the sun set (as it does every two weeks) they quickly died from the extreme cold—minus 62 F.
“Huddled together, the seedlings resembled a miniature, deep-green forest.”
– Marina Koren, “How Do Plants Grow in Space?” Jan 30, 2019, The Atlantic
The next step will be to build a sustainable garden on the moon or, better yet, Mars. Along these lines, NASA recently posted the finalists of the “BIG Idea Challenge 2019” to develop planetary greenhouse concepts. If you’d like to experiment on growing plants on the Red Planet, pick up some dirt from the Martian Garden. Students at Villanova who tried this in 2017 found that onions, garlic, kale and hops grew well, which would make an interesting diet for Mars colonists.
“Data are profoundly dumb”
Posted by mark in Basic stats & math, Uncategorized on October 22, 2018
This is the controversial view of Judea Pearl and Dana Mackenzie expressed in “Mind over Data”—the lead article in the August issue of Significance. In this excerpt from The Book of Why these co-authors explain “how the founders of modern statistics ‘squandered’ the chance to establish the science of causal inference”. They warn against “falsely believing the answers to all scientific questions reside in the data, to be unveiled through clever data-mining tricks.”
“Lucky is he who has been able to understand the cause of things.”
– Virgil (29 BC)
Pearl and Mackenzie are optimistic that the current “Causal Revolution” will lead to far greater understanding of underlying mechanisms. However, by my reckoning, randomized controlled trials remain the gold standard for establishing cause and effect relationships. Only then can the data speak loud and clear.
Technology advanced beyond any hope for healthy curiosity
I am watching the Syfy’s series “Childhood’s End” this week. It is based on a science fiction novel by British author Arthur C. Clarke, one of my favorites growing up. One of the main characters is a very bright boy who at the end of the premier episode last night becomes an astrophysicist, despite this scientific profession being made entirely superfluous by the advanced technology of the alien Overlords.
This morning Robert Scherrer, the chairman of the department of physics and astronomy at Vanderbilt University, lamented in an editorial* for Wall Street Journal that children no longer have any reason to be interested in science, mainly because most of our household gadgets fall into the category of magic—alluding to Clarke’s observation that “any sufficiently advanced technology is indistinguishable from magic.”
“The world’s now placid, featureless, and culturally dead: nothing really new has been created since the Overlords came. The reason’s obvious. There’s nothing left to struggle for, and there are too many distractions and entertainments.”
― Arthur C. Clarke, Childhood’s End
Are you a super-recognizer?
Every now and then I see someone in an airport or other public place who looks very familiar. Now and then I’ve actually walked up to someone and greeted them by name and gotten a blank, off-putting look in return. That is embarrassing! However, I feel vindicated today after taking this 5 minute web test for facial recognition and passing it with a grade (11 out of 15) that makes me a potential “super recognizer.” 🙂 The researchers at University of Greenwich asked me to follow up by taking a 45 minute test to verify my superior abilities, but I am going to quit while I’m ahead.
If you flunk this facial recognition test, you suffer from “prosopagnosia”—that would not be good because it indicates a poorly developed “fusiform” in the back of your brain. 🙁
For those who do qualify in the UG web quiz and take the longer test, the payoff could be a job with the crack team of super-recognizers at Scotland Yard. Read about them in this fascinating National Geographic post with the Gory Details on “Face Finding Superpower for Fighting Crime”.
Crater Experiment Makes a Big Impact
Posted by mark in design of experiments, science on June 25, 2015
Craters are crazy and cool. One that is quite amazing was created by the Barringer Meteorite that crashed into Arizona about 50,000 years ago with an explosion equal to 2.5 megatons of TNT. Based on this detailing of what a 2 MT bomb would do I figure that Barringer would have completely wiped out my home town of Stillwater, Minnesota and its 20,000 or so residents, plus far more beyond us. The picture my son Hank took of the 1 mile wide 570 foot deep crater does not do justice to its scale. You really need to go see it for yourself
as the two of us did.
Because of my enthusiasm for craters, making these rates number on my list of fun science projects in DOE It Yourself. As noted there, members the Salt Lake Astronomical Society wanted to drop bowling balls from very high altitudes onto the salt flats of Utah, but workers in the target area from the U.S. Bureau of Land Management objected to the experiment.
Kudos to science educator Andrew Temme for leading students through a far more manageable experiment shown in this video. In reply to me asking for permission for providing a link to his fantastic impact movies Andrew gave me this heads-up. “I attended a NASA workshop to get certified to handle real moon rocks and meteorites at the NJ State Museum in Trenton. This lab in the educator guide suggested mixing up your own lunar powder and throwing objects to simulate impact craters. When I got home I ran the lab with a few of my classes and then made the video. I used a Sony handheld camera that had a slow motion setting (300 fps).” Awesome!
The other day I went up to the 9th floor of my condo building in Florida and tossed a football down on to the parking lot. I am warming up to heaving a 15 pound mushroom anchor over on the beach side from atop one of the far pricier high rises along the Gulf. However, I have to wait until the turtle nesting season is over.
Pyrex—a miracle of material science—hits the century mark
A few years ago I dropped my cell phone and, to my great surprise, broke the Corning® Gorilla® glass display. This incident illustrates how far our expectations have come for what originally was an extremely fragile material. Tough glass is a very recent development that still falls a bit short—even the newest Gorilla Glass 4 survives drops only 80% of the time according to Corning. But give these material scientists a little more time. They are sure to do even better at making glass truly unbreakable and far more flexible to boot.
Resistance to temperature, on the other hand, is now a given with glass, in particular the brand Pyrex® introduced in 1915 by Corning. They quit manufacturing Pyrex in 1998 but you can still buy it, albeit in a cheaper form made from soda-lime rather than borosilicate.*
For the whole story, see Pyrex at 100 from the May 18th issue of Chemical and Engineering News (C&EN).
*(You are advised to read these shattering details from The American Ceramic Society on the consequences of going to the less-costly Pyrex.)
Believe it or not–sweet statistics prove that you can lose weight by eating chocolate
A very happy lady munching on a huge candy bar caught my eye in The Times of India on Friday, May 25. Not the lady—the chocolate.
After tasting a variety of delectable darks from a chocolatier in Belgium many years ago, I became hooked. However, I never imagined this addiction would provide a side benefit of weight loss. It turns out that a clinical trial set up by journalist John Bohannon and two colleagues came up with this finding and showed it to be statistically significant. This made headlines worldwide.
Unfortunately, at least so far as I’m concerned, the whole study was a hoax based on deliberate application of junk science done to expose phony claims made by the diet industry.
It turns out to be very easy to generate false positive results that favor a dietary supplement. Simply measure a large number of things on a small group of people. Something surely will emerge that out of this context tests significantly significant. What this will be, whether a reduction in blood pressure, or loss in weight, etc., is completely random.
Read the whole amazing story here.
My thinking is while Bohannan’s study did not prove that eating chocolate leads to weight loss, the subjects did in fact shed pounds faster than the controls. That is good enough for me. Any other studies showing just the opposite results have become irrelevant now—I will pay no attention to them.
Now, having returned from my travel to India, I am going back to dip into my horde of dark chocolate.
Too many tourists trying to occupy limited spaces
I spent the weekend in Prague attempting to relax after a stimulating two days attending the 2015 Camo User Meeting. It really was great except for the main sights of the city being so crowded with tourists like me.
The traffic patterns vary greatly by the intermittent busloads of tour groups—big bunches of Japanese or Americans and other places worldwide that come to this wonderfully historic city.
It turns out that there’s a universal power law governing pedestrian interactions according to studies led by the Director of the University of Minnesota’s Applied Motion Lab Stephen Guy. He and his collaborators have developed a novel statistical-mechanical approach to directly measure the interaction energy between pedestrians. Using this simple interaction law they can simulate crowd phenomena such as two tour groups crossing a city square or trying to push into a just-opened attraction. See these situations and others illustrated in CGI movies here.
All I can think of when viewing these simulations is how horrible it is to get caught up in a crowd. The saving grace is you needn’t think much when this happens—just let your natural collision-avoidance system take over and go on auto-pilot.
When you gotta glow, you gotta glow
In my youth I enjoyed a pop ditty by Johnny Mercer about a little glow worm. This song is now stuck in my head. It is an “ear worm”! It emerged from a corner of my brain when I toured the Waitomo Caves in the North Island of New Zealand yesterday and saw the wonderful constellations of glow worms that populate its cavern ceilings.
I have no clue how to eliminate an ear worm, but it turns out that glow worms are susceptible to increases in carbon dioxide according a poster presentation of this scientific study that kept me occupied while awaiting our Maori guide at the cave mouth. Not surprisingly the half million tourists get the most blame. It’d be far worse if not for the glowworms providing such a breathtaking sight.
Lightening up the load on birds and bees
My former neighbor Phil–a bee-keeper–told me he loaded up too many hives in his truck on a run to California and it went over-weight for the regulations on the road home. However, Phil beat the highway inspectors by banging on the side with a hammer as he drove onto the scale. The bees flew up in the air and took down the measurement just enough for a pass–avoiding a hefty fine.
I always wondered if Phil was ‘bee-essing’ me, but a recent study by a Stanford scientist, reported here by NewScientist, indicates that this trick might be bang on. The only catches are that the flyers (in this case Pacific parrotlets, must flap in synch and the weight must be taken on the upstroke. This whole idea would backfire badly on the downstroke when the weight of the flyers comes back double.
Bee-leave it or not.